ML23093A105
| ML23093A105 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 08/02/2023 |
| From: | John Lamb, Bo Pham Plant Licensing Branch II |
| To: | |
| References | |
| EPID L-2022-LLE-0020, NRC–2023–0091 | |
| Download: ML23093A105 (9) | |
Text
[7590-01-P]
NUCLEAR REGULATORY COMMISSION
[Docket No. 50-425; NRC-2023-0091]
Southern Nuclear Operating Company;
Vogtle Electric Generating Plant, Unit 2;
AGENCY: Nuclear Regulatory Commission.
ACTION: Exemption; issuance.
SUMMARY
- The U.S. Nuclear Regulatory Commission (NRC) has issued an exem ption
in response to a request dated June 30, 2022, as supplemented b y letters dated
September 13, 2022, and January 20, and May 5, 2023, from South ern Nuclear
Operating Company to allow the use of AXIOM fuel rod cladding material in lead test
assemblies 7ST1, 7ST2, 7ST3, and 7ST4, for up to two cycles of operation at Vogtle
Electric Generating Plant, Unit 2.
DATES: The exemption was issued on August 1, 2023.
ADDRESSES: Please refer to Docket ID NRC-2023-0091 when contacting the NRC
about the availability of information regarding this document. You may obtain publicly
available information related to this document using any of the following methods:
- Federal Rulemaking Website: Go to https://www.regulations.gov and
search for Docket ID NRC-2023-0091. Address questions about Docket IDs in
Regulations.gov to Stacy Schumann; telephone: 301-415-0624; ema il:
Stacy.Schumann@nrc.gov. For technical questions, contact the in dividual listed in the
For Further Information Contact section of this document.
- NRCs Agencywide Documents Access and Management System
(ADAMS): You may obtain publicly available documents online in the ADAM S Public
Documents collection at https://www.nrc.gov/reading-rm/adams.ht ml. To begin the search, select Begin Web-based ADAMS Search. For problems wit h ADAMS, please
contact the NRCs Public Document Room (PDR) reference staff at 1-800-397-4209, at
301-415-4737, or by email to PDR.Resource@nrc.gov. The ADAMS ac cession number
for each document referenced (if it is available in ADAMS) is p rovided the first time that it
is mentioned in this document.
- NRCs PDR: The PDR, where you may examine and order copies of publicly
available documents, is open by appointment. To make an appoint ment to visit the PDR,
please send an email to PDR.Resource@nrc.gov or call 1-800-397-4209 or 301-415-
4737, between 8 a.m. and 4 p.m. eastern time (ET), Monday throu gh Friday, except
Federal holidays.
FOR FURTHER INFORMATION CONTACT: John G. Lamb, Office of Nuclear Reactor
Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001;
telephone: 301-415-3100; email: John.Lamb@nrc.gov.
SUPPLEMENTARY INFORMATION: The text of the exemption is attached.
Dated: August 2, 2023.
For the Nuclear Regulatory Commission.
/RA/
John G. Lamb, Senior Project Manager, Plant Licensing Branch 2-1, Division of Operator Reactor Licensing, Office of Nuclear Reactor Regulation.
2 Attachment - Exemption from 10 CFR 50.46 for Vogtle, Unit 2, to Allow the Us e of AXIOM Fuel Rod Cladding Material in Lead Test Assemblies
NUCLEAR REGULATORY COMMISSION
Docket No. 50-425
Southern Nuclear Operating Company
Vogtle Electric Generating Plant, Unit 2
Exemption
I. Background.
Southern Nuclear Operating Company (SNC, the licensee) is the h older of
Facility Operating License No. NPF-81, for the Vogtle Electric Generating Plant (Vogtle),
Unit 2. The license provides, among other things, that the lice nse is subject to all rules,
regulations, and orders of the Commission now or hereafter in e ffect.
The Vogtle, Unit 2, consists of a pressurized-water reactor loc ated at the
licensees site in Burke County, Georgia.
II. Request/Action.
By letter dated June 30, 2022 (Agencywide Documents Access and Management
System (ADAMS) Accession No. ML22181B156), as supplemented by l etters dated
September 13, 2022 (ML22256A198), January 20, 2023 (ML23020A148 ), and May 5,
2023 (ML23125A269), SNC requested an exemption to title 10 of t he Code of Federal
Regulations (10 CFR), part 50, section 50.46, Acceptance criteria for eme rgency core
cooling systems for light-water nuclear power reactors, for Vo gtle, Unit 2.
3 Specifically, SNC requested an exemption from 10 CFR 50.46 to a llow the use of
AXIOM fuel rod cladding material in lead test assemblies (LTAs) 7ST1, 7ST2, 7ST3, and
7ST4 for up to two cycles of operation at Vogtle, Unit 2.
The regulation at 10 CFR 50.46(a)(1)(i) requires that, Each boiling or
pressurized light-water nuclear power reactor fueled with urani um oxide pellets within
cylindrical zircaloy or ZIRLO cladding must be provided with an emergency core cooling
system (ECCS) that must be designed so that its calculated cool ing performance
following postulated loss-of-coolant accidents conforms to the criteria set forth in
paragraph (b) of this section. The regulations make no provisions for use of fuel rods
clad in a material other than zircaloy or ZIRLO.
III. Discussion.
Pursuant to 10 CFR 50.12, the NRC may, upon application by any interested
person or upon its own initiative, grant exemptions from the re quirements of
10 CFR part 50, including 10 CFR 50.46, when: (1) the exemption s are authorized by
law, will not present an undue risk to the public health or saf ety, and are consistent with
the common defense and security; and (2) when special circumsta nces are present.
Under 10 CFR 50.12(a)(2), special circumstances include, among other things, when
application of the specific regulation in the particular circum stances would not serve, or
is not necessary to achieve, the underlying purpose of the rule.
4 A. The Exemption is Authorized by Law.
In accordance with 10 CFR 50.12, the NRC may grant an exemption from the
requirements of 10 CFR part 50 if the exemption is authorized b y law. The exemption
requested in this instance is authorized by law, because no oth er prohibition of law
exists to preclude the activities which would be authorized by the exemption.
This exemption would allow the licensee to insert four LTAs con taining AXIOM
fuel rod cladding that is neither Zircaloy nor ZIRLO, which are the cladding materials
contemplated by 10 CFR 50.46(a)(1)(i). Selection of a specific cladding material in
10 CFR 50.46 was at the discretion of the Commission consistent with its statutory
authority. No statute required the NRC to adopt this specificat ion. As stated above,
10 CFR 50.12 allows the Commission to grant exemptions from the requirements of
10 CFR part 50. The NRC staff has determined that granting of a n exemption from
10 CFR 50.46 related to AXIOM fuel rod cladding, which is neith er Zircaloy nor ZIRLO,
will not result in a violation of the Atomic Energy Act of 1954, as amended, or the
Commission's regulations. Therefore, the exemption is authorize d by law.
B. The Exemption Presents no Undue Risk to Public Health and Sa fety.
SNC stated the following in its letter dated June 30, 2022:
The Vogtle reactors each contain 193 fuel assemblies. Each asse mbly consists of a matrix of 264 Zircaloy, ZIRLO TM[], or Optimized ZIRLO[TM]
clad fuel rods with an initial composition of natural or slight ly enriched uranium dioxide (UO2) as fuel material, not to exceed 5 wt% [we ight-percent] enrichment. The proposed change is to load four LTAs w ith advanced ATF [accident-tolerant fuel] features, including ADOPT fuel [2],
AXIOM cladding [3], chromium coating, and four rods per LTA wit h up to 6 wt% enrichment, in limiting core locations for up to two cycl es of operation.
This exemption will not present an undue risk to public health and safety.
Reload evaluations ensure that acceptance criteria are met for the insertion of LTAs with fuel rods clad with AXIOM material. Due to similarities in the composition of the AXIOM alloy and the Opti mized 5
ZIRLO and standard ZIRLO alloys, fuel assemblies using AXIOM fu el rod cladding are evaluated using plant-specific models to address t he changes in the cladding material properties. The LOCA [loss-of-coolant accident] safety analyses for VEGP [Vogtle Electric Generating Plant] are supported by the applicable site-specific Technical Specificati ons (TS).
Reload cores are required to be operated in accordance with the operating limits specified in the TS. Thus, the granting of thi s exemption request will not pose an undue risk to public health and safety.1
Based upon the limited number of AXIOM clad fuel rods, the safe guards in place
which would detect anomalous behavior, the use of NRC-approved models to ensure
that all design criteria remain satisfied, and the requirement to operate the Vogtle, Unit 2,
core within TS limits, the NRC staff finds the four LTAs accept able for Vogtle, Unit 2. In
conclusion, the NRC staff finds t hat the requested exemption does not result in any
undue risk to the public health and safety, because NRC staff c oncluded that the existing
LOCA evaluation models analysis of records for Vogtle are repre sentative of the LTAs,
and the presence of the LTAs will have a negligible impact on t he co-resident fuel, and
10 CFR 50.46 acceptance criteria continue to be met. Further in formation can be found
in the NRC staff safety evaluation (ML23093A028).
C. The Exemption is Consistent with the Common Defense and Secu rity.
The proposed exemption would allow the use of four LTAs with a variant cladding
material. This change to the plant core configuration has no im pact on security issues.
Special nuclear material in the LTAs will continue to be handle d and controlled in
accordance with applicable regulations. Therefore, the common d efense and security is
not impacted by this exemption.
1 Although this quoted material states that the LTAs would be placed in limiting core locations, SNCs May 5, 2023, supplement, states that the LTAs will not be placed in core regions that have been shown to be limiting with respect to the control rod ejection analysis.
6 D. Special Circumstances
Special circumstances, in accordance with 10 CFR 50.12(a)(2)(ii ), are present
whenever application of the regulation in the particular circum stances would not serve
the underlying purpose of the rule or is not necessary to achie ve the underlying purpose
of the rule. The underlying purpose of 10 CFR 50.46 is to estab lish acceptance criteria
for ECCS performance. In the safety evaluation (SE) contained i n (ML23093A028) for
the license amendment request, the NRC staff evaluated for Vogt le, Unit 2, four LTAs
that demonstrated the acceptability of the AXIOM cladding under LOCA conditions. The
unique features of the LTAs were evaluated for effects on the L OCA analyses. The
results showed that the LTAs would not adversely affect ECCS pe rformance. Therefore,
the NRC staff concludes that application of the limitation to z ircaloy and ZIRLO in
10 CFR 50.46 in this particular circumstance is not necessary f or the licensee to achieve
the underlying purpose of the rule.
E. Environmental Considerations
With respect to its impact on the quality of the human environm ent, the NRC has
determined that the issuance of the exemption discussed herein meets the eligibility
criteria for categorical exclusion set forth in 10 CFR 51.22(c) (9). The NRC staffs
determination that all of the criteria for this categorical exc lusion are met is as follows:
The regulation 10 CFR 51.22(c)(9) states:
Issuance of an amendment to a permit or license for a reactor u nder part 50 or part 52 of this chapter that changes a requirement or iss uance of an exemption from a requirement, with respect to installation or u se of a facility component located within the restricted area, as defin ed in part 20 of this chapter; or the issuance of an amendment to a permit or license for a reactor under part 50 or part 52 of this chapter that changes an inspection or a surveillance requirement; provided that: (i) Th e amendment or exemption involves no significant hazards consider ation; (ii) There is no significant change in the types or significant increase in the amounts of any effluents that may be released offsite; and 7
(iii) There is no significant increase in individual or cumulat ive occupational radiation exposure.
Staff Analysis: The exemption is from requirements with respect to the
installation or use of facility components located within the r estricted area as defined in
10 CFR part 20. The criteria for determining whether an action involves a significant
hazards consideration are found in 10 CFR 50.92. The proposed a ction involves
installed four LTAs. As stated in the evaluation in ML23093A028, the Commission has
previously issued a proposed finding that the amendments involv e no significant hazards
consideration, published in the Federal Register on November 8, 2022 (87 FR 67508),
and there has been no public comment on such finding.
The proposed action involves installing four LTAs, and as the N RC staff
evaluated under the SE contained in ML23093A028, this action do es not involve any
significant change in the types or significant increase in the amounts of any effluents that
may be released offsite.
The proposed action involves installing four LTAs, and as the N RC staff
evaluated under the SE contained in ML23093A028, this action do es not involve any
significant increase in individual or cumulative occupational e xposure.
Based on the above, the NRC staff concludes that the proposed e xemption
meets the eligibility criteria for the categorical exclusion se t forth in 10 CFR 51.22(c)(9).
Therefore, in accordance with 10 CFR 51.22(b), no environmental impact statement or
environmental assessment need be prepared in connection with th e NRCs issuance of
this exemption.
IV. Conclusions.
Accordingly, the NRC has determined that, pursuant to 10 CFR 50.12, the
exemption is authorized by law, will not present an undue risk to the public health and 8
safety, and is consistent with the common defense and security. Also, special
circumstances, pursuant to 10 CFR 50.12(a)(2)(ii), are present. Therefore, the NRC
hereby grants SNC an exemption from the requirements of 10 CFR 50.46 to allow the
use of AXIOM fuel rod cladding material in LTAs, 7ST1, 7ST2, 7S T3, and 7ST4, for up
to two cycles of operation at Vogtle, Unit 2.
Dated at Rockville, Maryland, this 1 st day of August, 2023
For the Nuclear Regulatory Commission.
/RA/
Bo M. Pham, Director, Division of Operating Reactor Licensing, Office of Nuclear Reactor Regulation.
9